Pest Gallery

Termites: Isoptera

Termites primarily feed on wood, but also damage paper, books, insulation, and even swimming pool liners and filtration systems. Termites can injure living trees and shrubs, but more often are a secondary invader of woody plants already in decline. While homes may become infested at any time, termites are of particular importance when buying or selling a home since a termite inspection/infestation report is normally a condition of sale. Besides the monetary impact, thousands of winged termites emerging inside one’s home are an emotionally trying experience — not to mention the thought of termites silently feasting on one’s largest investment.

Spring typically is when large numbers of winged termites, known as “swarmers,” emerge inside homes. In nature, termites swarm to disperse and start new colonies. Triggered by warmer temperatures and rainfall, the winged termites emerge from the colony and fly into the air. The swarmers then drop to the ground, shed their wings, pair off with a mate, and attempt to begin new colonies in the soil. Few swarmers emerging outdoors survive to start new colonies. Swarmers emerging indoors are incapable of eating wood, seldom survive, and are best removed with a vacuum. They do, however, indicate that an infestation is present.

Discovering winged termites indoors almost always indicates an infestation warranting treatment. The swarmers are attracted to light and are often seen around windows and doors. If winged termites are seen emerging from the base of a foundation wall or adjoining porches and patios, there’s a good chance the house is infested also and treatment may be warranted. Other signs of infestation are earthen (mud) tubes extending over foundation walls, support piers, sill plates, floor joists, etc. The mud tubes are typically about the diameter of a pencil, but sometimes can be thicker.

Termites construct these tubes for shelter as they travel between their underground colonies and the structure. To help determine if an infestation is active, the tubes may be broken open and checked for the presence of small, creamy-white worker termites. If a tube happens to be vacant, it does not necessarily mean that the infestation is inactive; termites often abandon sections of tube while foraging elsewhere in the structure.

Termite-damaged wood is usually hollowed out along the grain, with bits of dried mud or soil lining the feeding galleries. Wood damaged by moisture or other types of insects (e.g., carpenter ants) will not have this appearance. Occasionally termites bore tiny holes through plaster or drywall, accompanied by bits of soil around the margin. Rippled or sunken traces behind wall coverings can also be indicative of termites tunneling underneath.